The disappearance of 3-year-old Madeleine McCann gained worldwide attention, but 12 years later there’s still no trace of her. We investigate what really happened to her and if she could still be alive. Then, a serial killer posing as a photographer leaves behind pictures of his possible victims: Can social media help investigators identify who they are?

Dr. Oz goes where he's never gone before. He's letting you eat fast-food and it's not what you expect. Learn which fast food meals you can eat under 500 calories while still enjoying the food you love.